In a known process to increase the aroma of vinegar, this is aged in wooden casks of oak, chestnut, juniper and similar to enhance the vinegar with the aroma that can be extracted naturally from the wood. Prolonged ageing is required to obtain appreciable aromas and this process is thus lengthy and costly and, owing to the high final cost of the product, can only be used for limited productions.
Aromatic vinegars obtained by using “cooked” or concentrated musts of grapes are known. These vinegars are known as “balsamic vinegar of Modena” and “traditional balsamic vinegar of Modena” and are essentially produced in the area of the Italian provinces of Modena and Reggio Emilia.
Traditional balsamic vinegar is produced by almost simultaneous alcoholic and acetic fermentation of grape musts previously cooked and concentrated over a direct flame. The musts are inoculated with yeasts, for alcoholic fermentation, and with bacteria, for acetic fermentation, and let to ferment in wooden containers until reaching the maximum degree of acidity obtainable from bacteria and yeasts. The steps of development and aging will then continue for at least 12 years; the steps require partial transferring of the product from one container to the other, with the dimensions of the containers decreasing as the product being processed ages. This process and the product obtained are particularly costly.
To obtain aromatic vinegars at lower costs processes have been developed in which aromatic compounds are added to a base vinegar; namely compounds able to give an aroma to vinegar; an example of this process is the production of (so-called industrial) balsamic vinegar of Modena in which cooked and concentrated musts are added to the vinegar to provide a product with an acidity (expressed in acetic acid) of at least 6% (grams per 100 ml) and a sugar content generally of at least 100-110 g/l. The quality of the product obtained can be improved by ageing and refining in wooden casks, to increase the concentration of sugars, aromatic compounds and density of the product; the known procedure of adding caramel to the product allows the desired colour to be obtained, but does not to improve the organoleptic properties of the product nor does it increase the content of sugar or aromatic compounds; and it also decreases the acidity of the product to the detriment of taste.
Another problem of this technique is the inevitable decrease in the acidity of the product during ageing or heating; in particular, it was found that an increase in the content of sugar and aromatic compounds corresponds to an acidity decrease from 6% to 4-4.5%. A balsamic vinegar with reduced acidity is less acceptable compared to a vinegar with an acidity of at least 6%.
Fruit aromatic vinegars (namely not wine vinegars) such as for instance apple, raspberry and similar vinegars are known as well. The aromatic component of these vinegars is given substantially by ester type compounds contained in fruits, therefore, in order to upgrade their organoleptic properties, even the aromatic component of these vinegars must be increased and improved.
The aim of the present invention is to solve the problems above mentioned and to provide a low-cost and quick process for the production of aromatic vinegars, especially balsamic or balsamic type vinegars of Modena, capable of providing products with an acidity of at least 6 g/100 ml and a high content of sugar and aromatic compounds, without adding sugar, alcohol or artificial aromas during acetic fermentation or the production process.
This aim is obtained by means of the present invention that relates to a process for the production of aromatic vinegar comprising the steps of mixing vinegar with must and characterised in that said vinegar is subjected to freeze concentration before mixing it with must.
According to a preferred embodiment of the invention, wine vinegar is concentrated and then assembled to, that is to say mixed together with, concentrated grape musts. The product thus obtained may then be used as it is, or submitted to a subsequent slow partial evaporation process while being heated under slow stirring.
According to another aspect of the invention, concentrated vinegar is produced without adding alcohol before, during or after the freeze concentration step.
The product obtained can reach high concentrations of sugars and natural aromatic products (esters and similar) and has exceptional organoleptic properties which can otherwise be obtained only by means of lengthy ageing processes.
Therefore, a further object of the invention is an aromatic vinegar as obtainable through the process described above and in particular an aromatic vinegar of the (industrial) “balsamic of Modena” type with an acidity of at least 6% and a sugar content of at least 400 g/l.
Another object of the invention is a freeze concentrated vinegar with an overall acidity expressed in acetic acid of at least 15% and preferably within the range between 18% and 25% (g/100 ml).
As mentioned, the invention has numerous advantages over the known techniques. In fact, it allows a product with high concentrations of sugar and aromatic compounds to be obtained in a very short time, when with traditional methods these concentrations can only be obtained with prolonged ageing of the product. Therefore, the costs are much lower compared with those of traditional products.
Another advantage lies in the fact that, with the same content of sugar and aromatic compounds as traditional aged products, aromatic vinegar according to the invention has an acidity of at least 6% or more and, therefore, a full and particularly pleasant taste. In particular, by performing freeze concentration of the wine vinegar alone and using concentrated musts available on the market it is possible to produce a vinegar according to the processes currently used to produce (industrial) balsamic vinegar of Modena and to obtain a product with much higher organoleptic characteristics than (industrial) balsamic vinegars of Modena available on the market.
Another advantage lies in the fact that the process is also suitable for the production of aromatic fruit vinegars. Yet another advantage lies in the fact that, thanks to freeze concentration, the contents of acidity and aromatic compounds in the initial vinegar remain essentially intact and, after freeze concentration, it has much greater concentrations of total acidity and aromatic compounds; this fact means that no additives of any type are required during production or fermentation of the initial vinegar.
Another advantage lies in the fact that freeze concentration causes a stabilization of the product due to a strong decantation of the substances that precipitate upon cooling.